Cybersecurity firm Crowdstrike is “actively working” to fix a “defect” in an update for Microsoft Windows users which sparked a global IT outage, the company’s chief executive has said.
CrowdStrike chief executive George Kurtz said Mac and Linux users were not impacted by the fault and it was “not a security incident or cyber attack”.
“The issue has been identified, isolated and a fix has been deployed,” Mr Kurtz wrote on X.
“We refer customers to the support portal for the latest updates and will continue to provide complete and continuous updates on our website.
“We further recommend organizations ensure they’re communicating with CrowdStrike representatives through official channels. Our team is fully mobilized to ensure the security and stability of CrowdStrike customers.”
Whitehall crisis officials are co-ordinating the response to the outage.
The Cobra system that deals with matters of national emergency or major disruption has been fired up, Chancellor of the Duchy of Lancaster Pat McFadden said.
Ministers are in touch with their sectors to tackle the fallout from the IT failures, with Transport Secretary Louise Haigh saying she is working “at pace with industry” after trains and flights ground to a halt.
Major infrastructure ground to a halt after computer systems were knocked offline, and devices were showing the so-called “blue screen of death”, affecting key sectors across the country.
The outage was “causing disruption in the majority of GP practices” in England but there was no known impact on 999 or emergency services, NHS England said.
The health service said patients should attend appointments unless told otherwise and should only contact their GP in urgent cases.
Across England, GP surgeries reported being unable to book appointments or access patient records as their EMIS Web system went down.
The National Pharmacy Association (NPA) said “services in community pharmacies, including the accessing of prescriptions from GPs and medicine deliveries, are disrupted today”.
In a statement, Microsoft said: “We are aware of an issue affecting Windows devices due to an update from a third party software platform. We anticipate a resolution is forthcoming.”
In the UK, Sky News went off air, and Britain’s biggest train company warned passengers to expect disruption because of “widespread IT issues”, as did many major airlines and airports.
Around the world, banks, supermarkets and other major institutions reported computer issues disrupting services, while many businesses were unable to take digital payments.
Overnight, Microsoft warned of “service degradation” which meant users were not able to access many of the tech giant’s most popular services and apps, used by millions of businesses and people around the world.
Among the impacted firms was Ryanair, with the airline posting to its website: “Potential disruptions across the network (Fri 19 July) due to a global third party system outage.
“Affected passengers will be notified and any passengers travelling across the network on Fri 19 July should check their Ryanair app for the latest updates on their flight.
“We advise passengers to arrive at the airport three hours in advance of their flight to avoid any disruptions.
“We regret any inconvenience caused to passengers by this third party IT issue, which is outside of Ryanair’s control and affects all airlines operating across the network.”
Airports and other airlines around the world reported major issues processing passengers with long queues forming at terminals and some flights grounded.
Govia Thameslink Railway – parent company of Southern, Thameslink, Gatwick Express and Great Northern – warned passengers to expect delays.
Service status monitoring website Downdetector said users were reporting issues with Visa, BT, major supermarket chains, banks, online gaming platforms and media outlets.
GP practices across England warned they could not access EMIS Web, the most widely used clinical system for primary care in the UK.
It enables GP practices to book appointments and examine records, and includes a clinical decision support tool as well as helping with admin.